Fluidized bed device and method for coating particles or granulation

Abstract

The present invention relates to a fluidized bed apparatus and a method for particle-coating or granulating, the fluidized bed apparatus includes a swirl generator which is mounted on a sprayer body in the fluidized bed apparatus and extends throughout an air distribution plate and is connected to a source of compressed air. The swirl generator comprises a tubular sleeve extending circumferentially around the sprayer body, and an air chamber is defined between the sleeve and the sprayer body, wherein the sleeve comprises a plurality of guiding slots. The air from the source of compressed air via the air chamber is directed by said guiding slots to rotate outwardly, so as to provide a swirling air stream circumferentially outwardly relative to the sprayer. The present invention can facilitate the development of the spray pattern and the particle flow pattern and allows the particles to spin respectively due to slight friction with the inner wall of the partition, thereby opportunities for the particles to obtain a more uniform spray when subsequently passing through the spray zone above the nozzle are increased, so that performance of the fluidized bed apparatus is improved.